Make crumble topping and set aside. Put the flour into a bowl. cut the butter into small pieces, add with the flour and rub it in with your fingertips until the mixture resembles fine breadcrumbs.

To make the muffins, sift together the flour, baking powder, baking soda, and salt into a large bowl. Stir in the sugar.Lightly beat the eggs in a large bowl, then beat in the yogurt, oil and vanilla extract. Make a well in the center of the dry ingredients, pour in the beaten liquid ingredients and add the raspberries. Stir gently until just combined;do not overmix.

Spoon batter into the prepared muffin pan (greased or paper liners). Scatter the crumble topping over each muffin and press down lightly. Bake in the preheated oven for about 20 minutes, until well risen, golden brown, and firm to the touch.